SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b814fded1ddcf982c5d3ca829834dfd0c3c15197df930f72cf4350743bca6606' 
  AND token = '80qKoONSJMUKsQj6MnbcJ1egxF2vjM9B7jDP0Byrngo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}